Semiconductor photoresist composition and method of forming patterns using the composition

This application claims priority to and the benefit of Korean Patent Application No. 10-2022-0096208, filed in the Korean Intellectual Property Office on Aug. 2, 2022, the entire content of which is incorporated herein by reference.

One or more embodiments of the disclosure relate to a semiconductor photoresist composition and a method of forming patterns utilizing the same.

EUV (extreme ultraviolet) lithography has been drawing much attention as an important or essential technology for manufacturing a next generation semiconductor device. The EUV lithography is a pattern-forming technology utilizing an EUV ray having a wavelength of 13.5 nm as an exposure light source. According to the EUV lithography, it is known that an extremely fine pattern (e.g., less than or equal to 20 nm) may be formed in an exposure process during a manufacture of a semiconductor device.

The extreme ultraviolet (EUV) lithography is realized through development of compatible photoresists which can be performed at a spatial resolution of less than or equal to 16 nm. Currently, efforts to overcome insufficient specifications of chemically amplified (CA) photoresists such as a resolution, a photospeed, and feature roughness (also referred to as a line edge roughness or LER) for the next generation device are desired and/or being continuously made.

An intrinsic image blurring due to an acid catalyzed reaction in polymer-type or kind photoresists limits a resolution in small feature sizes, which has been well known in electron beam (e-beam) lithography for a long time. The chemically amplified (CA) photoresists are designed for high sensitivity, but because their typical elemental composition reduces light absorbance of the photoresists at a wavelength of 13.5 nm and thus decreases their sensitivity, the chemically amplified (CA) photoresists may have more difficulties under an EUV exposure.

In addition, the CA photoresists may also have problems in making the small feature sizes due to roughness issues. The line edge roughness (LER) of the CA photoresists experimentally turns out to be increased, as a photospeed is decreased, partially due to an essence of acid catalyst processes. Accordingly, a novel high-performance photoresist is required, desired, and/or needed in a semiconductor industry because of these defects and problems of the CA photoresists.

To overcome the aforementioned drawbacks of the chemically amplified (CA) organic photosensitive composition, an inorganic photosensitive composition has been researched. The inorganic photosensitive composition is mainly utilized for negative tone patterning having resistance against removal by a developer composition due to chemical modification through nonchemical amplification mechanism. The inorganic composition contains an inorganic element having a higher EUV absorption rate than hydrocarbon and thus may secure sensitivity through the nonchemical amplification mechanism and is less sensitive to a stochastic effect, and thus can have low line edge roughness and small number of defects.

Inorganic photoresists based on peroxopolyacids of tungsten mixed with tungsten, niobium, titanium, and/or tantalum have been utilized as radiation sensitive materials for patterning.

These materials are effective for patterning large pitches for a bilayer configuration for far ultraviolet (deep UV), X-ray, and electron beam sources. More recently, when cationic hafnium metal oxide sulfate (HfSOx) materials along with a peroxo complexing agent are utilized to image a 15 nm half-pitch (HP) through projection EUV exposure, desired performance has been obtained. This system appears to exhibit the highest performance of a non-CA photoresist and has a practical photospeed near to a requirement for an EUV photoresist. However, the hafnium metal oxide sulfate materials having the peroxo complexing agent have a few practical drawbacks. First, these materials are coated in a mixture of corrosive sulfuric acid/hydrogen peroxide and have insufficient shelf-life stability. Second, a structural change thereof for performance improvement as a composite mixture is not easy. Third, development is performed in a TMAH (tetramethylammonium hydroxide) solution at an extremely high concentration of 25 wt % and/or the like.

Recently, active research has been conducted on molecules containing tin that have excellent or suitable absorption of extreme ultraviolet rays. As for an organic tin polymer among them, alkyl ligands are dissociated by light absorption or secondary electrons produced thereby, and are cross-linked with adjacent chains through oxo bonds and thus enable the negative tone patterning that may not be removed by an organic developing solution. The organic tin polymer exhibits significantly improved sensitivity as well as maintains suitable resolution and line edge roughness, but the patterning characteristics need to be further improved for commercial availability.

One or more aspects of embodiments of the present disclosure are directed toward a semiconductor photoresist composition capable of implementing a pattern with significantly improved sensitivity, resolution, and storage stability.

One or more aspects of embodiments of the present disclosure are directed toward a method of forming patterns utilizing the semiconductor photoresist composition.

Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.

According to one or more embodiments, a semiconductor photoresist composition may include a first organometallic compound represented by Chemical Formula 1, a second organometallic compound represented by Chemical Formula 2, and a solvent.

In Chemical Formula 1 and Chemical Formula 2,

In one or more embodiments, Rin Chemical Formula 1 may be a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C1 to C20 alkoxy group, or a combination thereof,

In one or more embodiments, the first organometallic compound may be represented by Chemical Formula 1-1 or Chemical Formula 1-2.

In Chemical Formula 1-1 and Chemical Formula 1-2,

In one or more embodiments, Rin Chemical Formula 2 may be a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C1 to C20 alkoxy group, or a combination thereof,

In one or more embodiments, the second organometallic compound may be represented by any one selected from among Chemical Formula 2-1 to Chemical Formula 2-4.

In Chemical Formula 2-1 to Chemical Formula 2-4,

In one or more embodiments, X, X, Y, Y, Z, and Zmay each independently be —ORor —OC(═O)R,

In one or more embodiments, *-L-Rin Chemical Formula 1 may be a tert-butyl group, a tert-pentyl group, a tert-hexyl group, a tert-heptyl group, a tert-octyl group, a tert-nonyl group, or a tert-decyl group, and

In one or more embodiments, the first organometallic compound and the second organometallic compound may be included in a weight ratio of about 99.9:0.1 to about 50:50.

In one or more embodiments, the first organometallic compound and the second organometallic compound may be included in a weight ratio of about 99:1 to about 70:30.

In one or more embodiments, based on 100 wt % of the semiconductor photoresist composition, a total amount of the organometallic compound including the first organometallic compound and the second organometallic compound may be about 0.5 wt % to about 30 wt %.

In one or more embodiments, the semiconductor photoresist composition may further include an additive of a surfactant, a crosslinking agent, a leveling agent, or a combination thereof.

According to one or more embodiments, a method of forming patterns may include forming an etching target layer on a substrate, coating the semiconductor photoresist composition on the etching target layer to form a photoresist layer, patterning the photoresist layer to form a photoresist pattern, and etching the etching target layer utilizing the photoresist pattern as an etching mask.

The photoresist pattern may be formed utilizing light in a wavelength of about 5 nm to about 150 nm.

The method of forming patterns may further include providing a resist underlayer formed between the substrate and the photoresist layer.

The photoresist pattern may have a width of about 5 nm to about 100 nm.

The semiconductor photoresist composition according to one or more embodiments may provide a photoresist pattern having improved sensitivity, resolution, and storage stability.

The present disclosure may be modified in many alternate forms, and thus specific embodiments will be exemplified in the drawing and described in more detail. It should be understood, however, that it is not intended to limit the present disclosure to the particular forms disclosed, but rather, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure.

Hereinafter, referring to the drawings, embodiments of the present disclosure are described in more detail. In the following description of the present disclosure, the well-established functions or constructions will not be described in order to clarify the present disclosure.

In order to clearly illustrate the present disclosure, throughout the disclosure, the same or similar configuration elements are designated by the same reference numerals. Also, because the size and thickness of each configuration shown in the drawing are arbitrarily shown for better understanding and ease of description, the present disclosure is not necessarily limited thereto.

In the drawings, the thickness of layers, films, panels, regions, etc., may be exaggerated for clarity. In the drawings, the thickness of a part of layers or regions, etc., may be exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present.

As utilized herein, “substituted” may refer to replacement of a hydrogen by deuterium, a halogen, a hydroxy group, a cyano group, a nitro group, —NRR′ (wherein, R and R′ may each independently be hydrogen, a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group), —SiRR′R″ (wherein, R, R′, and R″ may each independently be hydrogen, a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or a substituted or unsubstituted C6 to C30 aromatic hydrocarbon group), a C1 to C30 alkyl group, a C1 to C10 haloalkyl group, a C1 to C10 alkylsilyl group, a C3 to C30 cycloalkyl group, a C6 to C30 aryl group, a C1 to C20 alkoxy group, or a combination thereof. “Unsubstituted” may refer to non-replacement of a hydrogen by another substituent and remaining of the hydrogen.

As utilized herein, when a definition is not otherwise provided, “an alkyl group” may refer to a linear or branched aliphatic hydrocarbon group. The alkyl group may be “a saturated alkyl group” without any double bond or triple bond.

The alkyl group may be a C1 to C10 alkyl group. For example, the alkyl group may be a C1 to C8 alkyl group, a C1 to C7 alkyl group, a C1 to C6 alkyl group, a C1 to C5 alkyl group, or a C1 to C4 alkyl group. For example, the C1 to C4 alkyl group may be a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, or a 2,2-dimethylpropyl group.

As utilized herein, when a definition is not otherwise provided, “cycloalkyl group” may refer to a monovalent cyclic aliphatic hydrocarbon group.

The cycloalkyl group may be a C3 to C10 cycloalkyl group, for example, a C3 to C8 cycloalkyl group, a C3 to C7 cycloalkyl group, a C3 to C6 cycloalkyl group, a C3 to C5 cycloalkyl group, or a C3 to C4 cycloalkyl group. For example, the cycloalkyl group may be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, or a cyclohexyl group, but is not limited thereto.

As utilized herein, “aryl group” may refer to a substituent in which all atoms in the cyclic substituent have a p-orbital and these p-orbitals are conjugated and may include a monocyclic or fused ring polycyclic functional group (i.e., rings sharing adjacent pairs of carbon atoms).

As utilized herein, when a definition is not otherwise provided, “alkenyl group” may refer to an aliphatic unsaturated alkenyl group including at least one double bond as a linear or branched aliphatic hydrocarbon group.

As utilized herein, unless otherwise defined, “alkynyl group” may refer to an aliphatic unsaturated alkynyl group including at least one triple bond as a linear or branched aliphatic hydrocarbon group.

In the formulas described herein, t-Bu may refer to a tert-butyl group.

Hereinafter, a semiconductor photoresist composition according to one or more embodiments will be described in more detail.

In one or more embodiments, the semiconductor photoresist composition may include a first organometallic compound, a second organometallic compound, and a solvent.